“We’ve been engineering our tails off to bring you the best personal 3D printer and we rejected the proprietary cartridge model for printing materials which other companies use, because we encourage sharing and iteration,” MakerBot founder Bre Pettis wrote last week on the MakerBot Industries blog.

He was turning his nose up at the ink cartridge model, whereby manufacturers hold consumers hostage by charging them stiff prices for ink cartridges to keep their printers printing. Besides running out of ink too quickly, the cartridges also contain chips to monitor use, Mr. Pettis wrote. “This is such an old, accepted model of doing business, we don’t even think about it anymore. Razor blades, ink cartridges, photo printers, Swiffers, and mobile phones & service contracts. That’s the old world. That’s a wasteful world.”

Unfortunately, that attitude may be creeping into the 3D printing industry.

The 3D printing ecosystem is taking off, and more competitors are slipping into the space. The Cube, which starts at a very affordable $1,299, is the tiny, slick, Wifi-enabled printer that has some pundits speculating it may be the first 3D printer to appeal to the mainstream consumer. The Cube uses proprietary printer cartridges, with plastic available in ten colors. “With our EZ load Cartridge changing to a different color or replacing an empty cartridge is a breeze,” Cube says on its site.

It may be EZ, but it’s not open, maker movement purists say. “I know it’s an odd balance between wanting 3D Printing to go mainstream by making it extremely user-friendly and removing barriers, but when you hand me closed up cartridges of filament and everything is ‘pop it in and go, replace through our store using our proprietary fittings and canisters’ it feels really foreign to the whole Maker movement,” user Tim Owens commented on the post.

MakerBot sells cartridges as well, but its printers can take generic cartridges. UPDATE: MakerBot printers use spools of plastic, not cartridges, which package the plastic in a closed container.

“3D Systems and Stratasys are using a business model that is familiar from the copy machine days. Just get ‘em on the toner. Stratasys just released a new product last week, the Mojo, with a $10K price point. The plastic, however, runs $400 for a 3lb spool — allegedly,” another source in the 3D printing industry told Betabeat on background. “What’s happening here is that their cartridges are ‘easy load’, but they also have a special printhead on them. If you don’t have that printhead, you can’t use the machine. The other worry is that your cartridge could be monitoring your plastic usage using an internal chip.”

The release of the Mojo may have been the catalyst for Mr. Pettis’s post (just guessing!). The razor blade/ink cartridge approach is unlikely to go over well with the open source soldiers of the 3D printing revolution, but it may not be as much of a sticking point for the general population. As long as our printer lets us load chocolate cartridges, we’re good.

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